鸭梨联胎现象的初步研究

A Preliminary Study on the Duplicata Phenomenon of Pyrus bretschneideri Rehd.f. Ya-li Yu

鸭梨品质优良 ,为原产我国的著名品种 ,分类上属白梨系统 ,也是驰名中外的亚洲良种梨 ,品系繁多。研究认为 ,有的品系在果心腔内残留的一小真果是联胎现象造成的结果 ,对此尚未见有关植物胚胎学方面的报道。在植物形态学上研究 ,此小真果是属于只有雌蕊没有雄蕊和花被的一朵不完全花未经受精的子房残留物 ,内有干瘪种子 ;是白梨在演化过程中由单生花序到总状花序间的杯状聚伞花序的一个过渡类型 ;也是联胎现象造成的一种特殊类型。这一发现对白梨野生种的研究有重要意义 ,对生产上鲜果品质的选择也具有一定价值。因目前对联胎发生过程尚未有足够的研究 。

Ya li(Pyrus bretschneideri Rehd.f. Ya li Yu) is an old famous pear variety originated from China, also a superior variety in Asia. There are many cultivars in Ya li system.Through preliminary study, there found a residuary small true fruit within the core cavity of the pseudocarp of some cultivars of Ya li,which is resulted from the duplicata phenomenon. So far, no embryological research on this phenomenon has been reported. According to the morphological study, the small true fruit is resulted from an incomplete flower,which only has the ovary and style,and the ovary has not been fertilized,so this residue only has the young ovary with styles and some shrunken seeds.This special small true fruit induced by duplicata phenomenon is an interim type of inflorescence between the monochasium and raceme cup shaped cyme. This discovery is important for studying the wild species of P. bretschneideri Rehd.,and also of some value for selecting good quality fresh pome of Ya li. Due to limited research has been addressed on the duplicata phenomenon, so no complete conclusion on its origin can be made yet.